Double-sided pressure-sensitive adhesive tapes are used for fixing parts in the fields of electrical, electronic, or OA appliances, home electrical appliances, aircrafts, ships, vehicles, etc.
As a result of the remarkable progress of investigations and applications of electronics and of semiconductor and magnetic-body technology in recent years, the high integrations, size reductions, and performance advancements in electrical, electronic, and OA appliances, etc. have been proceeding, and the risk of firing due to the elevated temperature and heat accumulation (thermal storage) inside such appliances is increasing. From the necessity of preventing such risk, the various components within the appliances and the parts used for bonding the components have come to be required to have a high level of flame retardance. Meanwhile, also in the fields of home electrical appliances, aircrafts, and the like, various investigations are being enthusiastically made on the flame-proofing of plastic materials, and adhesive materials to be used for fixing these materials have, of course, come to be required to have high flame retardance.
Especially in the field of aircrafts, among these, an exceedingly high level of flame retardance is required of even the adhesives and pressure-sensitive adhesives for use in fixing parts, etc. Furthermore, with respect to double-sided pressure-sensitive adhesive tapes for use in fixing the carpets and the like of aircrafts, from the standpoint of working efficiency, it is required to be able to be easily and cleanly torn by hand without using any edged tool. In addition, since parts such as carpets are periodically replaced, there is a desire for a double-sided pressure-sensitive adhesive tape that has pressure-sensitive adhesive properties sufficient for use but that can be easily removed at the time of replacement and does not cause the so-called adhesive remaining, which is the phenomenon in which a pressure-sensitive adhesive residue remains on the floor or wall after the removal.
As a double-sided pressure-sensitive adhesive tape having flame retardance, for example, in patent document 1, there is proposed a flame-retardant double-sided pressure-sensitive adhesive tape comprises: a substrate sheet in which a substrate sheet constituted of a nonwoven polyester fabric having a basis weight of 15-80 g/m2 is impregnated with a composition for impregnation which includes a pressure-sensitive adhesive and an organic flame retardant of nitrogen system and which further contains a flame retardant that contains none of the halogens, antimony, and phosphorus; and pressure-sensitive adhesive layers coated on both sides of the substrate sheet respectively, the pressure-sensitive adhesive layers being constituted of a flame-retardant pressure-sensitive adhesive composition in which 20-200 parts by mass of a flame retardant that includes an organic flame retardant of nitrogen system but contains none of the halogens, antimony, and phosphorus is added to 100 parts by mass of an acrylic pressure-sensitive adhesive.